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    <script>
        let arr = ['短跑','接力','短跑','拔河','跳绳','接力','跳绳','拔河','跳远']
        function unique(arr){
            let newArr = []
            for (let i = 0; i < newArr.length; i++) {
                if (newArr.indexOf(arr[i]) === -1) {
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